PERTH has sweltered through its hottest night on record, and total fire bans are in place across the state in response to a continuing heatwave.

Temperatures in Perth peaked at more than 43C on Saturday, and dipped to a still-steamy low of 29.7C just after 3am this morning.

That beat the previous record of 29.3C in 1962. The mercury rose again to 39.7C in the city just after 9am.

More than 30 career and volunteer Fire and Rescue Service and Bush Fire Service firefighters worked overnight to put out a scrub fire near a University of Western Australia research facility at Jolimont, in the city's west.

One staff member had to be evacuated but no buildings were damaged, although some fences were destroyed.

Department of Fire and Emergency Services said about 30 hectares were burnt, but the fire was contained and under control early on Sunday.

Residents in Jolimont and Shenton Park were told to stay alert and take care when driving through the area.

The cause of the fire is being investigated.

Elsewhere, more than 100 Bush Fire Service and Department of Parks and Wildlife firefighters from Boddington, southeast of Perth, were fighting a fire near Pinjarra-Williams Road, and two hectares were burnt near Caversham Wildlife Park, north of the city.

The Bureau of Meteorology has forecast an extreme fire danger on Sunday for Perth, Mandurah, the Perth Hills, and parts of the Great Southern and the Upper Great Southern.

A total fire ban is in place for parts of the Midwest Gascoyne and Great Southern.

Fines up to $25,000 or jail sentences of up to 12 months apply if a total fire ban is ignored.

Perth swelters through hottest January day in 23 years

PERTH sweltered through its hottest January day in 23 years yesterday when the mercury peaked at 43.3C.

It was also the hottest day in Perth since Boxing Day 2007, when a maximum of 44.2C was recorded.

But the hottest temperature measured in the state - and, indeed, on the whole planet - was in the Mid-West town of Morawa, 370km north of Perth. The town's 500-plus residents had to contend with a searing 46.9C at 3.45pm.

The electricity grid took a pounding as residents bunkered down with their airconditioning cranked up.

News_Image_File: Perth Zoo has started handing out monster icy poles and other iced treats to animals to help the animals beat the heat. Picture: Perth Zoo

Perth Zoo has distributed monster icy poles to its animals, with even the otters enjoying icy poles made from whitebait, blue bait, prawns and mussels.

News_Image_File: Perth Zoo has started handing out monster icy poles and other iced treats to animals to help the animals beat the heat. Picture: Perth Zoo

Even fortunate pool and spa owners were being warned to take precautions, with a reminder to ensure water was properly treated so swimmers avoid catching amoebic meningitis, which thrives in water temperatures between 28 and 40 degrees.

The scorching temperatures will arise as a pocket of very hot air, which has subjected the Pilbara to intense heat this week, begins to move south.

Onslow has suffered through two successive days over 40C, with Paraburdoo topping 40C by 9.30am on Friday.

Mike Burgin, regional director from the Bureau of Meteorology, said Saturday was likely to be Perth's hottest day since Boxing Day, 2007.

"And Perth certainly won't be the worst of it. To the north-east of the city we will get temperatures up to 46, 47 degrees,'' he said.

Ascot race meeting first casualty of heat

ASCOT'S race meeting became the first casualty of tomorrow's scorching 44C day as Perth looks for ways to beat the heat.

It has been a busy start to the Surf Life Saving season since patrols began in October, with 696 rescues, 1207 first-aid treatments and an additional 5827 actions taken to prevent incidents.

There have also been four coastal drowning deaths at unpatrolled spots.

Surf Life Saving WA community safety manager Chris Peck said it was crucial that beach-goers swam between the red and yellow flags, and followed the advice of lifesavers.

He said people also needed to be "beach safe'' by supervising children, having aquatic skills, knowing first aid and CPR, and using appropriate safety gear and planning for emergencies.

"It is also vital that in hot conditions beach-goers regularly apply sunscreen, keep hydrated and remember that consumption of alcohol impairs physical responses and decision-making processes, and anyone that has consumed alcohol should not enter the water,'' Mr Peck said.

All major Perth beaches will be patrolled by Surf Life Saving services and Wesfarmers Lifesaver Jet-Ski teams over the weekend, as well as aerial surveillance between Yanchep and Mandurah by the Westpac Lifesaver Helicopter.

Sunday won't provide much relief, with an expected top of 39C but the weather shapes up nicely from Monday with expected tops in the low 30 for the first half of the week.

The beach is expected to be a popular place as Perth tries to beat the heat tomorrow.

IT didn't quite reach 50C yesterday but it's unlikely the good folk of Learmonth and Onslow really noticed the difference as the mercury maxed at over 48C.

The Pilbara's mega heatwave continued yesterday - at Onslow Airport, almost 1400km north of Perth, the temperature reached 48.2C at about 12.30pm.

Learmonth Airport, near Exmouth and about 1250km north of Perth, was fractionally behind, recording a high of 48.1 just before 2.30pm.

The Bureau of Meteorology has been unable to obtain information from Emu Creek, where it was forecast to reach 49C and possibly threaten 50C.

Onslow has roasted through two of its hottest days on record, with temperatures soaring to 48.7C yesterday, closely followed by today's 48.2C.

Today, Learmonth had the highest maximum in the Pilbara, peaking at 46.9C just after 2.30pm, while the mercury reach 45C in Paraburdoo.

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